Tektronix DC 502, Instruction Manual

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Operating Instructions —DC 502
Contact
28B
27A
27B
26A
25A
25B
24B
23B
22B
20B
20A
21B
19A
19B
Assignment
Second decimal point (D2) output.
Internal scan clock disable input.
MHz light output.
Reset input/output.
TS0 (Time Slot Zero) output.
External scan clock input.
Internal scan clock (2 kHz) output.
Overflow output.
MSD (Most Significant Digit) output.
8
4
2
1
BCD output, serial by digit.
Data good output.
Fig. 1-3. Input/Output pin assignments at rear connector.
Rear Connector I/O Assignments
Input and output data access to the DC 502 is available
at the rear of the main circuit board. Fig. 1-3 identifies the
contacts and their respective I/O assignments. A Power
Module mainframe option is available which provides a
rear-panel, multi-pin connector to which these data can be
hard-wired for external access. Also possible are intra­
compartment connections with other plug-in modules when
using a multi-compartment Power Module.
SPECIFICATIONS
Option 1—Precision Time Base
The DC 502 can be ordered with a temperature-
compensated 5-MHz crystal oscillator to provide a highly
stable (5 parts in 107 ) and precise internal time base. This
option includes a divide-by-five 1C counter to produce the
1-MHz clock.
Measurement Ranges, Resolution, and Accuracy
Frequency, 10 Hz to 550 MHz; Gate times, 0.01 s, 0.1 s,
1 s, and 10 s; Display time, about 0.1 s to 10 s to HOLD;
Totalizing capacity, 0 to 107; Resolution (DIRECT
INPUT), 100 Hz at 0.01 s gate time, 10 Hz at 0.1 s, 1 Hz at
1 s, and 0.1 Hz at 10 s; Resolution (4-10 PRE-SCALE
INPUT), 1000 Hz at 0.01 s, 100 Hz at 0.1 s, 10 Hz at 1 s,
and 1 Hz at 10 s; Accuracy, ±1 count ± time base accuracy.
Direct Input
Frequency, 10
Hz to 110 MHz;
Sensitivity, 300
mV
peak-to-peak;
Trigger level range,
±2 V;
Attenuators,
X1,
X5, X10, and X50; Coupling, AC; Input impedance,
approximately 1 MΩ paralleled by about 20 pF; Maximum
input volts, 500 V (DC + peak AC, or peak-to-peak AC).
÷10 Pre-Scale Input
Frequency, 50 MHz to 550 MHz; Sensitivity, 500 mV
peak to peak;
Coupling,
AC;
Input impedance,
approxi ­
mately 50 Ω; Maximum input volts, 10 V peak-to-peak.
Data
Inputs and Outputs
Available via plug-in connector to multi-pin connector at
rear of Power Module. Input lines are available for internal
and external scan clock control. Output lines are available
for
BCD output (serial-by-digit), and to indicate status of
timing, data good, reset, scale, decimal point and overflow.
Internal Time Base
Standard
Option 1
Crystal Frequency
1 MHz 5 MHz
Stability (0°C to
+50°C), after 1/2
hour warm-up
Within 1 part in
10 5
Within 5 parts in
10 7
Long-term Drift
1 part or less in
105 per month
1 part in
107 per month
Accuracy Adjustable to
within 1 part in
107
Adjustable to
within 5 parts in
109
Other
Temperature Range,
Operating: 0°C to +50°C; Non­
operating: —40°C to +75°C.
Altitude Range,
Operating: to 15,000 feet; Non- )
operating: 50,000 feet.
1-4
REV. MAY 1974
®2